Buy a professional digital outer diameter micrometer online, the measuring range is 3~4", the digital micrometer gauge measures in millimeters and inches, and the large screen clearly provides digital readings. This digital outer diameter micrometer can also be used for accurate measurement in harsh environments measurement.
Tips: How to calibrate a digital micrometer?
When checking whether the zero position of the digital micrometer is calibrated, the screw and the measuring anvil should be in contact, occasionally it may happen that the two do not separate when the force-measuring device is rotated backward. In this case, the left palm of the left hand can be used to press against the left side of the anvil on the ruler frame, the right palm of the right hand can be pressed against the force measuring device, and then the knob can be turned in the counterclockwise direction with the fingers to separate the screw and the anvil.